A toxic scare at a school in Colorado that saw dozens of students having to be decontaminated and several taken to hospital with skin and eye irritation, may have been caused by one of the world's hottest chillies.

An investigation into the incident, which led Jefferson County Open School to be evacuated, found pieces of habanero peppers in the playground.

The chilli is so hot people handling them wear gloves.

Image Caption:The school was evacuated after children complained of burning eyes

In a statement, Melissa Reeves for Jefferson County Public Schools, said: "In searching the playground area, employees found pieces of approximately six habanero peppers scattered in the wood chips.

"Coming in contact with the pepper oil would cause many of the symptoms that students experienced.

"District teams are in the process of washing the playground equipment and wiping down surfaces inside to ensure that the school is free of any residual pepper oil.

"The wood chips in the area where the peppers were found are being replaced."

It is not known how the peppers got onto the playground.

Image Caption:A decontamination tent was set up at the scene of the toxic outbreak

Around 30 students and a teachers' assistant had to be washed down by firefighters on Monday, after children started complaining of burning eyes and skin irritation.

Seven were treated in hospital.

One young girl said: "They had to hose down my head. It was really cold."

A firefighter dealing with the incident said: "We had different hits of some toxic irritant type stuff.

"We have ruled out fertiliser which was some of the initial reports, as the soccer field directly north of the school did have fertiliser applied."